Iyo is a city located in Ehime Prefecture, Japan.
On February 2009, the city has an estimated population of 39,915 and a population density of 205.25 persons per km². The total area is 194.47 km².
On April 1, 2005, Iyo absorbed the towns of Nakayama and Futami to create the new and expanded city of Iyo, raising its population to over 40,000 and nearly quadrupling its area.